import java.util.Scanner;
public class str {
    public static void main(String[] args) {
        String name= "justin";
        System.out.println(name);
        System.out.println(name.length());
        System.out.println(name.charAt(0));
        System.out.println(name.toUpperCase());
        Scanner scanner = new Scanner(System.in);
        long sum =0;
        long number =0 ;
        do{
            System.out.print("请输入数字：");
            number = Long.parseLong(scanner.nextLine());
            sum +=number;

        }while (number!=0);
        System.out.println("总和： "+sum);

    }
}
